How to Wash a Sleeping Bag | Hand Wash AND Machine Wash

Your sleeping bag is going to get dirty. It’ll be there alongside you forging through hot, cold, wet, and dry conditions. It will be keeping you cozy on weekend getaway... or a 6 month thru-hike.

Either way, it’s inevitable that it will need some freshening up. In doing so, you can actually revitalize your bags loft and insulation.

IMPORTANT. You need to wash your bag properly. The wrong approach could lead to:

1. Tears: Sleeping bags are delicate, so washing them in a cramped washer or in one that’s a top-loader with a built-in agitator can tear your bag.
2. Loss of loftiness: Washing with the wrong detergent or not following the manufacturer's care instructions can risk stripping down important oils that keep your bag properly lofting.
3. Clumps: Getting your bag twisted in the washer, or wringing it out when it's wet can cause the fill to clump together which will affect the bag's insulation.
4. Melting: Drying your bag with the right heat setting is important to keep it from melting. If it’s in the dryer, frequently inspecting your bag for any crinkling, melting or hot spots is a good precaution.

In this article, we'll show you how to wash your sleeping bag step by step and have it come out in better shape than it went in.

Synthetic vs. Down Sleeping Bags

SYNTHETIC

You can wash synthetic bags with a mild non-detergent soap or an agent that’s tailored for synthetic material. Just be sure to run the bag through an additional rinse cycle—whether using a machine or washing by hand—to ensure all the soap gets washed out. Otherwise, the fill can mat up, affecting the bag's overall insulation.

DOWN

Because down is fussier when wet, it’s a bit more tedious to clean than synthetic. Down bags should be washed less often, if possible, and they’ll require specifically formulated soap, like Nikwax Down Wash that won’t strip out oils. It's also a good idea to rinse out your detergent dispenser to remove old detergent residues before using it. Lastly, down bags should be dried with a few tennis balls to help them loft properly. 

METHOD A: How to MACHINE WASH Your Sleeping Bag

Machine washing is less labor-intensive than hand-washing. It’s an effective way to evenly clean your entire bag at the end of a season. However, compared with hand-washing, this method is likely to reduce your sleeping's longevity.

INSTRUCTIONS (STEP-BY-STEP)

1. Put your sleeping bag in the washer
2. Add the appropriate laundry detergent. Slightly less than the normal dose. Do not use fabric softener or bleach.
3. Choose a slow-speed, delicate cycle. Set the temperature to the setting recommended on the product tag. 
4. Run the rinse cycle twice to make sure you get all the detergent out

Washing instructions on the Montbell Down Hugger sleeping bag

To reduce the risk of damage to your sleeping, do the following first:

• Give the bag’s care instructions a good read to make sure it can be machine washed
• Check for tears or holes and repair them first if there are any
• Loosen any drawstring
• Close all zippers, Velcro and buttons
• Turn your sleeping bag inside out

LOAD TYPE: FRONT-LOADING VS. TOP-LOADING

• Front-Loading: When washing your sleeping bag, use a front-loading machine if you can. Front-loaders operate by tumbling clothes and are known to be more gentle than top-loading alternatives. After hand-washing, front-loading machines are the safest way to ensure your bag doesn't get torn or ripped during the washing cycle.
• Top-loading (with agitator): Agitators are spinner rods commonly found in top-loading washing machines. Avoid those at all costs. They usually have fins or blades that help move the water and clothes around the washer. While they might sound like a good idea, agitators have a reputation for being rough on fabrics and will damage your sleeping bag.
• Top-loading (with impeller): Impellers are more like spinning discs and do not have a rod. If you're going to use a top-loading washer, make sure that it uses an impeller, not an agitator. Impellers move the clothes around the machine using water pressure, and are therefore considered a lot gentler. This makes them better suited for washing delicate items like sleeping bags.

WASHER SIZE: THE BIGGER THE BETTER

A cramped sleeping bag won't be washed properly and could lose some of its loft and insulation in the process. You want to use a washing machine that is large enough so that your sleeping bag can comfortably waltz around the drum. 

If your home washer is either too small or uses an agitator, your best bet is to head to the local laundromat and snag the largest front-loading washing machine they have.

Sleeping bag in a top-loading impeller washing machine.

METHOD B: How to HAND WASH Your Sleeping Bag

Hand-washing lets you zone-in on dirty spots or stains, and it’s a safer way to wash your bag with extra care if you’re worried about it getting ripped.

INSTRUCTIONS (STEP-BY-STEP)

1. Fill a (clean) bathtub with warm water and mix in your recommended specialty down or synthetic cleaner
2. Place your bag in the tub and scrub both ends of the bag, carefully massaging water and the cleaning agent through the bag
3. Spot clean any areas that have stains or spills with a soft toothbrush
4. Let the bag soak for 30 minutes to an hour
5. Fill the tub with clean water and gently massage the bag again. Repeat several times until you've washed all the soap out. You can check to make sure by pressing down on the bag and seeing if any suds surface.
6. Firmly press as much of the remaining water out of the bag as you can. Don’t wring it out or lift the bag. Stepping on it in the bathtub works well.

Spot cleaning a sleeping bag with a soft toothbrush

How to DRY Your Sleeping Bag

When it's time to get your bag out of the tub or washer, carefully move it with both hands placed underneath it. Grabbing the bag from one end while it's wet may cause the seams to break. Then, follow one of these drying methods:

OPTION A: HANG DRYING

Hang-drying a sleeping bag takes a couple of days. It's slow, but it’s the safest way to make sure the insulation and outer shell don’t get damaged by heat.

When you hang it (on a clothesline, over a rope, spread out across chairs, etc.), make sure it’s not in a spot that’s directly in the sun. The UV rays can damage the nylon.

Wait 48 hours for it to dry completely.

OPTION B: USING A DRYER

Need your bag faster? Throw it in a front-load dryer and tumble dry it on the lowest setting. If you don’t have one at home, dryers at the local laundromat can fit the bill.

You’ll want to dry your bag on the lowest heat setting and leave plenty of room in the dryer so the bag can spread out. Also, don’t use dryer sheets.

An excellent trick to keep the insulation from clumping up with down is to throw in a few tennis balls when the bags about 75% dry for the rest of the cycle. Tennis balls aren’t needed for synthetic bags.

Drying will take about an hour for a synthetic bag and two or three times longer for a down bag.

Carry your sleeping bag with both hands so that the seams don't break.

Storage

The last thing you want to do is store your bag when wet. Not only will it not loft or insulate properly, but it can breed mildew and it’ll stink. Make sure it's fully dry before putting it away. It's a good habit  to always air your bag out for at least 24 hours following a trip or washing.

It’s also better to never store your bag in a stuff sack, as this can compress the insulation and make the bag lose its loft faster. Instead, store your sleeping bag somewhere cool and dry where it can spread and air out like hung in a closet or loosely folded in a large mesh bag.

Sleeping bag stored in mesh bag

FAQ

How often should I wash my sleeping bag?

This can vary by use. But even if you’re the type that spends more time outdoors in a sleeping bag than in your bed, giving your bag a thorough washing at the end of every season to rid it of dirt, body oils, and… umm… smell… is a good rule of thumb ;)

How do I keep the bag clean longer?

1. Sleep in clean clothes: Sleeping bags tend to absorb sweat and dirt. By changing into clean clothes before climbing into your sleeping bag, you can prolong time between washes. If you're wondering what to wear, you can't go wrong with a set of merino wool baselayers.

2. Use a sleeping bag liner: Liners only weigh a few ounces, and using one can keep the inside of your bag clean and protect it against dirt, grime, body oils, and tears. Here are some models that we like. 

Can a sleeping bag be dry-cleaned?

Unless you're sending your bag to a specific sleeping bag dry cleaner (ie REI’s Rainy Pass Repair, Inc), most dry cleaners are a gamble. Many won’t have the right detergents, and the wrong ones can do more harm than good. But if you don’t have a front load washer/dryer or access to one, then this might be your best option. Always check to be sure the company knows how to clean bags properly. It’ll usually cost you around $60, give or take, and there could be long lead times depending on the season.

Are sleeping bags waterproof?

Most sleeping bags already come treated with a DWR (durable water repellent) agent applied to the fabric. You can tell the DWR is still working when water beads up and rolls off your sleeping bag instead of seeping through. Naturally, the agent wears off over time and will need to be re-applied.

If you drop some water on your bag and it seeps in instead of rolling off, it’s time for another treatment. Nikwax or a spray-on option found at your local outdoor shop should do the trick.